test java.nio.file.Files.walkFileTree(Path, Set<FileVisitOption>, int,
FileVisitor<? super Path>) and java.nio.file.Files.walk(Path, int,
FileVisitOption...) methods.

Signed-off-by: Flycoding <Flycoding@yeah.net>
test PathMatcher.

Signed-off-by: Flycoding <Flycoding@yeah.net>
test java.nio.file.FileSystem.supportedFileAttributeViews().

Signed-off-by: Flycoding <Flycoding@yeah.net>
test other methods.

Signed-off-by: Flycoding <Flycoding@yeah.net>
add a WatchService java test.

Signed-off-by: Flycoding <Flycoding@yeah.net>